Spectacle lens arrangements have already been proposed in the prior art. As a rule, such spectacle lenses have an input coupling portion in an edge region of the spectacle lens arrangement. Moreover, provision is made of an output coupling portion in a central region or lenticular region of the spectacle lens arrangement. Then, the spectacle lens is suitable for guiding a light beam of a produced image, which is coupled into the spectacle lens arrangement by way of the input coupling portion, in the spectacle lens arrangement up to the output coupling portion and for coupling said light beam out of the spectacle lens by way of the output coupling portion. As a rule, internal total-internal reflection is used for guidance between the input coupling portion and the output coupling portion. A Fresnel surface structure may be provided for providing the output coupling portion, for example.
For instance, the document DE 10 2013 219 626 A1 shows an example of such a lens arrangement. This document discloses a spectacle lens for a display apparatus that can be placed onto the head of a user and that produces an image, having a spectacle lens body having a front side and a rear side, wherein the front side and/or the rear side is/are curved and the spectacle lens body has at least one first and one second partial body, the interfaces of which facing one another being in direct contact, and having, as seen in a plan view of the spectacle lens, an input coupling portion in an edge region of the spectacle lens and an output coupling portion in a central region of the spectacle lens, wherein the spectacle lens is suitable for guiding light beams of pixels of the produced image, which are coupled into the spectacle lens by way of the input coupling portion of the spectacle lens, in the spectacle lens up to the output coupling portion and to couple said light beams out of the spectacle lens by way of the output coupling portion, wherein provision is made in the spectacle lens body of a plane first reflection area and a plane second reflection area spaced apart from the first reflection area, said reflection areas each extending in a direction from the input coupling portion to the output coupling portion and each being spaced apart from the front and rear side of the spectacle lens body, wherein the light beams are guided in the direction from the input coupling portion to the output coupling portion by way of reflections at the two reflection areas and wherein at least one of the first and second reflection area is provided in the first or second partial body and offset from the interface of the corresponding partial body in a direction from the first to the second partial body.
Optical elements should often be joined in such spectacle lens arrangements. Here, it may be the case that a plurality of optical elements have to be joined, for example a plurality of lens elements to one another or a film, shell or a further optical element on the lens element. When the optical elements are joined thus using an adhesive, the conditions in an edge region are often decisive for the success of the adhesion process. If too much adhesive is provided in an adhesion gap between the elements to be joined, the adhesive emerges from the sides. If too little adhesive is provided, the edge regions of the joining portion are not filled in an ideal manner. This may be accompanied by significant impairments of subsequent processes if there is no uniform connection and support of the optical elements over the joining area. When joining, no contaminations may arise during the joining process. Moreover, the appearance of cavities or edge regions that are not completely wetted constitutes an obstacle for subsequent wet treatments. Under certain circumstances, subsequent processing steps may even become impossible. The amount of adhesive to be applied depends on the gap width, i.e. the distance between the joining elements, the geometric tolerances of the joining elements and also the accuracy of the application of adhesive. On account of this multiplicity of parameters, the exact application of the required amount of adhesive is connected with difficulties.
Moreover, there is within the spectacle lens arrangement an output coupling portion, as described above, which may be embodied as a Fresnel surface structure. The clear spaces necessarily arising when forming the Fresnel surface structure, which are referred to below as incision regions, should be filled with an optically neutral material in order to avoid unwanted optical effects such as image distortions, for example. Such a process may occur under reduced pressure or under positive pressure; it may also occur in different gas atmospheres, such as in an inert gas, for instance nitrogen, or another protective gas, for example. On account of the form, the small dimensions and the geometry of the Fresnel sloped elevations and the incision regions situated therebetween, air inclusions may form during filling and/or the filler material, which may also be an adhesive, for example, may not flow uniformly into the incision regions.